I make slab built platters and shallow bowls using cone 6 clay and glazes. I like a flat bottom, no foot look but not the resulting large expanse of bare clay on the bottom of the piece. I am wondering whether spraying the unglazed bottom with a solid coating of a solution of clear frit would enhance the aesthetics and long term functionality.
The frit solution would be applied after the final glaze firing. I am thinking of using a solution of Ferro Frit 3124 or 3134. The pieces would then be fired upside down (glazed surface against the shelf) to the melting temperature of the frit which would be in the range of 1450 - 1600 degrees F (cone 016 - 012). I am thinking the cone 5-6 glaze would not soften at these temperatures so the glazed areas against the shelf should not be a concern.
It would require an additional firing so obviously not feasible for production pottery but would it make sense for low volume decorative pieces?